The Mill uses Houdini February 2, 2008

In the end, the final look of the Tipping Point ad is a testament to the creative vision and skill of the team which resulted in a commercial that is spell binding in its impact on viewers. That achievement is all the more remarkable when one considers the tight twelve week time frame in which the production was completed while bringing to life the vision of the director.

“In the past, I had always thought about making a jump to Houdini because of its reputation as a powerful CG animation tool,” said Bares. “After using it, I realize how on certain projects I have been throwing away time writing scripts to solve production problems. Now I see that Houdini’s node-based approach is great to use period. I expect we will be seeing a steady stream of work from The Mill that uses Houdini.”

A Growing Appreciation for a Powerful Tool

The team at The Mill was pleased to see that the ramp-up time to learn Houdini was modest. An experienced Houdini artist was brought in to do the initial TD work based on pre-production plans. At the same time, he worked with the other team members to quickly get their Houdini skills productionready.

As familiarity with Houdini grew, initial plans to only use it for a small part of the pipeline was adjusted to give it a bigger role in order to better meet production requirements.

“I initially wanted to do the inner structure of the pint shot in Softimage XSI. I then realized that it was much faster to set things up in Houdini before transferring to XSI for geometry tweaking,” said Bares. “We built a very sophisticated proprietary import/export system so we could transfer geometry, particles, fluids, and hair from Maya to Houdini and back again and from XSI to Houdini and back again. This lets us to work with whichever tool is best suited to the job at hand.”

“From the beginning, we anticipated scrutiny from the client, director and agency when it came to creating the look of a Guinness pour using a tower of books,” said Jordi Bares, Joint-Head of 3D of The Mill’s London-based studio. “We needed to manage more than 60,000 CG objects, each controlled by multiple variables, while maintaining the ability to respond to client feedback.”

Using Houdini meant that the team could accommodate changes such as making the pint taller , adding more books, or creating more pages per book. For example, the ability to shift timing elements and speed in specific rows played a major role in helping to create the stop and start characteristic in the sequence that imitated the Guinness two-part pour.

“We found out very soon that we had to do the final scene in 3D. Tests involving our CG team, a concept artist and matte painter showed us that the shot was complex but do-able,” said Bares. “By rigging up the whole structure in Houdini, we could make very accurate changes. For example, Houdini let us set up specific controls for the number of pages per book and the speed at which they turned. This had a tremendous impact on the overall feeling of the shot.”

“We were able to tie in the start and stop pattern of the pour into the rig by adding per row control. Each book would find out which row it was in, read the right parameters for that row’s control and act according to instruction.” said Bares. “Even though this was one of the most difficult, jobs I have ever worked on, using Houdini gave us control over timing and speed and ultimately made the project pretty easy to manage.”

By taking advantage of Houdini’s procedural architecture, the team was able to explore creative ideas throughout the production process without ever writing a single script. They were able to load over 60,000 objects and easily manipulate them in 3D. The team also usedHoudini Mantra to render the shot and was able to build a fast and effective rendering process that helped make sequence visualization quick and detailed.

“Manipulating this many objects would have been a huge challenge in either Maya or XSI,’ said Bares.“And Mantra was able to render the whole lot in no time which made me very happy.”

Getting the perfect pour on a pint of Guinness is considered part art; part science. Animators at The Mill faced a similar challenge when asked to create a Guinness pour out of thousands of books with flipping pages for the commercial “Tipping Point.”

Set in an Argentinean mountain village, the commercial follows an elaborate domino project that starts in a small house then grows to include everything from wheels to cars to flaming bales of hay. The action then culminates in a three dimensional tower of books where the pages flip in sequence to create a dramatic working model of the classic Guinness pour.

Built-in Flexibility

The team had initially planned to shoot the first few books on location then use CG to complete the shot. After a few days on set, the team quickly realized that the high altitude of 3200 m made it virtually impossible to create a real working model of the structure. The complete effect would therefore need to be created using CG. To establish a flexible process capable of meeting creative demands, the team chose to model, rig and render the Guinness tower shot in Houdini 9.